   * {
            box-sizing: border-box;
        }
        body {
            margin: 0; 
            padding: 0;
            font: 16px/20px microsft yahei;
        }
        .wrap {
            width: 100%;
            height: 100%;
            position: fixed;
            opacity: 0.8;
            background: linear-gradient(to bottom right,#50a3a2,#53e3a6);
            background: -webkit-linear-gradient(to bottom right,#50a3a2,#53e3a6);
        }
        .container {
            width: 60%;
            margin: 0 auto;
        }
        .container h1 {
            margin-top: 250px;
            text-align: center;
            color: #FFFFFF;
            font-weight: 500;
        }
        .container input {
            width: 320px;
            display: block;
            height: 36px;
            border: 0;
            outline: 0;
            padding: 6px 10px;
            line-height: 24px;
            margin: 32px auto;
            -webkit-transition: all 0s ease-in 0.1ms;
            -moz-transition: all 0s ease-in 0.1ms;
            transition: all 0s ease-in 0.1ms;
        }
        .container input[type="text"] , .container input[type="password"]  {
            background-color: #FFFFFF;
            font-size: 16px;
            color: #50a3a2;
        }
        .container input[type='submit'] {
            font-size: 16px;
            letter-spacing: 2px;
            color: #666666;
            background-color: #FFFFFF;
        }
        .container input:focus {
            width: 400px;
        }
        .container input[type='submit']:hover {
            cursor: pointer;
            width: 400px;
        }

        .wrap ul {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: -10;
        }
        .wrap ul li {
            list-style-type: none;
            display: block;
            position: absolute;
            bottom: -120px;
            width: 15px;
            height: 15px;
            z-index: -8;
            background-color:rgba(255, 255, 255, 0.15);
            animotion: square 25s infinite;
            -webkit-animation: square 25s infinite;
        }
        .wrap ul li:nth-child(1) {
            left: 0;
            animation-duration: 10s;
            -moz-animation-duration: 10s;
            -o-animation-duration: 10s;
            -webkit-animation-duration: 10s;
        }
        .wrap ul li:nth-child(2) {
            width: 40px;
            height: 40px;
            left: 10%;
            animation-duration: 15s;
            -moz-animation-duration: 15s;
            -o-animation-duration: 15s;
            -webkit-animation-duration: 15s;
        }
        .wrap ul li:nth-child(3) {
            left: 20%;
            width: 25px;
            height: 25px;
            animation-duration: 12s;
            -moz-animation-duration: 12s;
            -o-animation-duration: 12s;
            -webkit-animation-duration: 12s;
        }
        .wrap ul li:nth-child(4) {
            width: 50px;
            height: 50px;
            left: 30%;
            -webkit-animation-delay: 3s;
            -moz-animation-delay: 3s;
            -o-animation-delay: 3s;
            animation-delay: 3s;
            animation-duration: 12s;
            -moz-animation-duration: 12s;
            -o-animation-duration: 12s;
            -webkit-animation-duration: 12s;
        }
        .wrap ul li:nth-child(5) {
            width: 60px;
            height: 60px;
            left: 40%;
            animation-duration: 10s;
            -moz-animation-duration: 10s;
            -o-animation-duration: 10s;
            -webkit-animation-duration: 10s;
        }
        .wrap ul li:nth-child(6) {
            width: 75px;
            height: 75px;
            left: 50%;
            -webkit-animation-delay: 7s;
            -moz-animation-delay: 7s;
            -o-animation-delay: 7s;
            animation-delay: 7s;
        }
        .wrap ul li:nth-child(7) {
            left: 60%;
            animation-duration: 8s;
            -moz-animation-duration: 8s;
            -o-animation-duration: 8s;
            -webkit-animation-duration: 8s;
        }
        .wrap ul li:nth-child(8) {
            width: 90px;
            height: 90px;
            left: 70%;
            -webkit-animation-delay: 4s;
            -moz-animation-delay: 4s;
            -o-animation-delay: 4s;
            animation-delay: 4s;
        }
        .wrap ul li:nth-child(9) {
            width: 100px;
            height: 100px;
            left: 80%;
            animation-duration: 20s;
            -moz-animation-duration: 20s;
            -o-animation-duration: 20s;
            -webkit-animation-duration: 20s;
        }
        .wrap ul li:nth-child(10) {
            width: 120px;
            height: 120px;
            left: 90%;
            -webkit-animation-delay: 6s;
            -moz-animation-delay: 6s;
            -o-animation-delay: 6s;
            animation-delay: 6s;
            animation-duration: 30s;
            -moz-animation-duration: 30s;
            -o-animation-duration: 30s;
            -webkit-animation-duration: 30s;
        }

        @keyframes square {
            0%  {
                    -webkit-transform: translateY(0);
                    transform: translateY(0)
                }
            100% {
                    bottom: 400px;
                    transform: rotate(600deg);
                    -webit-transform: rotate(600deg);
                    -webkit-transform: translateY(-500);
                    transform: translateY(-500)
            }
        }
        @-webkit-keyframes square {
            0%  {
                -webkit-transform: translateY(0);
                transform: translateY(0)
            }
            100% {
                bottom: 400px;
                transform: rotate(600deg);
                -webit-transform: rotate(600deg);
                -webkit-transform: translateY(-500);
                transform: translateY(-500)
            }
        } 